4道SAT数学选择题练习(二).

　　下面是为大家准备的4道SAT考试数学选择题练习题。同学们在备考SAT数学的过程中，一定要加强习题的练习，熟练到能充分理解题意，争取得到满分。

　　1.Miguel iscentimeters tall. At 2:00 p.m. one day, his shadow iscentimeters long, and the shadow of a nearby fence post iscentimeters long. In terms of, what is the height, in centimeters, of the fence post?

　　(A)

　　(B)

　　(C)

　　(D)

　　(E)

　　2.What is the equation of the line parallel to the -axis and four units above the -axis?

　　(A)

　　(B)

　　(C)

　　(D)

　　(E)

　　3.The stopping distance of a car is the number of feet that the car travels after the driver starts applying the brakes. The stopping distance of a certain car is directly proportional to the square of the speed of the car, in miles per hour, at the time the brakes are first applied. If the car’s stopping distance for an initial speed ofmiles per hour isfeet, what is its stopping distance for an initial speed ofmiles per hour?

　　(A)feet

　　(B)feet

　　(C)feet

　　(D)feet

　　(E)feet

　　4.If , , and are numbers such that and , then is equal to which of the following?

　　(A)

　　(B)

　　(C)

　　(D)

　　(E)

　　参考答案及解析：

　　1.The correct answer is C

　　Explanation

　　The situation described in the question can be pictured as in the figure below, where is the height, in centimeters, of the fence post.

　　There are two right triangles in the figure. One triangle is formed by part of the line from the sun to point , the perpendicular from Miguel’s head to the ground, and Miguel’s shadow along the ground. The other triangle is formed by part of the line from the sun to point , the perpendicular from the top of the fence post to the ground, and the fence post’s shadow along the ground. Since these two right triangles share the acute angle at , they are similar triangles. Since the corresponding sides of similar triangles are in proportion, it follows that. Solving this equation for , the height, in centimeters, of the fence post, yields .

　　2.The correct answer is E

　　Explanation

　　A line that is parallel to the-axis and four units above the-axis is the vertical translation of the-axis four units upward. Since the-axis is a horizontal line and has equation, it follows that the line parallel to the-axis and four units above the-axis has equation.

　　3.The correct answer is D

　　Explanation

　　The stopping distance is directly proportional to the square of the initial speed of the car. If represents the initial speed of the car, in miles per hour, and represents the stopping distance, you have that the stopping distance is a function of and that , where is a constant. Since the car’s stopping distance is feet for an initial speed of miles per hour, you know that . Therore, , and the car&aposs stopping distance for an initial speed of miles per hour is feet.

　　4.The correct answer is A

　　Explanation

　　From is implied that (1)

　　And from is implied that (2)

　　If we multiply (1) and (2) together, we have that ( is canceled out).

　　以上就是关于4道SAT考试数学选择题练习题及其答案和解析，非常详细。同学们在备考阶段，一定要加强习题的练习以及题意的理解，争取SAT数学满分。

　　下面是为大家准备的4道SAT考试数学选择题练习题。同学们在备考SAT数学的过程中，一定要加强习题的练习，熟练到能充分理解题意，争取得到满分。

　　1.Miguel iscentimeters tall. At 2:00 p.m. one day, his shadow iscentimeters long, and the shadow of a nearby fence post iscentimeters long. In terms of, what is the height, in centimeters, of the fence post?

　　(A)

　　(B)

　　(C)

　　(D)

　　(E)

　　2.What is the equation of the line parallel to the -axis and four units above the -axis?

　　(A)

　　(B)

　　(C)

　　(D)

　　(E)

　　3.The stopping distance of a car is the number of feet that the car travels after the driver starts applying the brakes. The stopping distance of a certain car is directly proportional to the square of the speed of the car, in miles per hour, at the time the brakes are first applied. If the car’s stopping distance for an initial speed ofmiles per hour isfeet, what is its stopping distance for an initial speed ofmiles per hour?

　　(A)feet

　　(B)feet

　　(C)feet

　　(D)feet

　　(E)feet

　　4.If , , and are numbers such that and , then is equal to which of the following?

　　(A)

　　(B)

　　(C)

　　(D)

　　(E)

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